Topic: Fluid Mechanics
A manometer is used to measure the pressure of a gas in a tank. The fluid used has a specific gravity of 0.85 and the manometer column height is 55 cm, as shown in figure. If the local atmospheric pressure is 96 kPa, what is the absolute pressure in the tank?
- A. 4.6 kPa
- B. 98.6 kPa
- C. 100.6 kPa
- D. 200 kPa
Answer: C. 100.6 kPa
Explanation: The density of the manometer fluid is 0.85 * 1000 = 850 kg/m³. The gauge pressure exerted by the fluid column is P_gauge = rho * g * h = 850 * 9.81 * 0.55 = 4586.175 Pa ≈ 4.6 kPa. The absolute pressure in the tank is P_atm + P_gauge = 96 kPa + 4.6 kPa = 100.6 kPa.